Whenever I try to run the BOINC screensaver, it flashes, flickers and judders insanely. How can I make it run properly?
Also, is there a way to tell it that I only want to see the SETIsaver?
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Whenever I try to run the BOINC screensaver, it flashes, flickers and judders insanely. How can I make it run properly?
Also, is there a way to tell it that I only want to see the SETIsaver?

The last question first: Since you are running several projects, no, you cannot show the SETI screen saver only. You can, however go to the settings for the BOINC screen saver and show only the project screen savers.

As for the first question: We probably need some more information about the problem. Which portion of the screen saver is running at the time?
____________BOINC WIKI

Very probably some background program is interfering, something that uses/probes the video card.
It may be some Gadget or Hardware Monitoring program that shows GPU related things (e.g. MHz, used VRAM, Temperatures).
Or some media player.
Or some program that want (is set) to be 'On-Top' (so it try to be 'On-Top' the screensaver (and all screensavers also try to be 'On-Top' of everything so they 'fight'))